10 PLAYFUL IDEAS

to make a child's occasional visit very special

W hen grandparents and single parents have only a limited time with their young relatives--say, a child for a day--every moment is precious.

"I went there with my Grandmother" or "I did that with my Dad" are words that make the waiting and planning worthwhile.

So, make your time count. Share the wonder, excitement and fun of new places and new experiences with your tots-to-teens. The following 10 activities are guaranteed memory-makers--and they're free!

Fire Stations. From about 8 a.m.-5 p.m., including weekends, children can sit behind the wheel of a fire engine, hop into a fireman's boots, try on his helmet, jacket and pants. Fireman will show youngsters the hose tower, air tanks and nets. Call (213) 485-5971 for the address of the fire station nearest you and be sure that your local unit is not out on routine exercises or an emergency.

Cabrillo Marine Museum, 3720 Stephen White Drive, San Pedro, (213) 548-7562. Hours: Tuesday-Friday noon-5 p.m., weekends 10 a.m.-5 p.m. Parking is $3, except free for scheduled tours. Discover the underwater world of Southern California's coast. At the Sandy Beach Wave Tank, see how some plants and animals live in the pounding surf while others live on the rocky shoreline, in mud flats and the ocean. Children can lift weights to feel how strong small sea animals really are; they can finger sandpapery sharkskin and a soft sea-otter pelt. At the Touch Tank, they can stroke slimy slugs, crusty starfish and prickly sea urchins. Slide shows and special events are scheduled daily.

drilling rig and other machinery that was used in farming, lumbering, mining and construction. Hundreds of other pieces of machinery ring the main area of this 40-acre working farm. Visit the museum, blacksmith shop and farmhouse. A small park has two swings and picnic tables.

El Dorado Park East Nature Center, 7550 E. Spring St., Long Beach, (213) 425-8569. Museum hours: Monday-Friday 10 a.m.-4 p.m., Saturdays and Sundays 8 a.m.-4 p.m., but starting Jan. 1 museum will close on Mondays. Trail hours: daily 8 a.m.-4 p.m.; closed Christmas. Parking: weekdays $1.50, weekends $2. First, touch crinkly skin shed by gopher snake and feel the smooth antlers of a deer in the Nature Center. The one- and two-mile self-guided tours are enriched by pamphlets that point out special sights along well-marked paths. People with walking or sight difficulties can take a special one-fourth-mile paved walk complete with a Trail Board written in Braille. Picnic at the end of the parking area or in adjacent El Dorado East Regional Park, which has a playground, bike path and four fishing lakes.

Sand Dune Park, 33rd Street at Bell Avenue, Manhattan Beach, (213) 545-5621. Climb and slide on a steep sand dune. The top can be reached by climbing the dune or by taking a winding path of steps. Bring a large piece of cardboard to slide on. Two enclosed play areas for tots and not-yet-teens offer swings, climbing bars and conventional slides. The tree-shaded picnic area has tables, barbecues, sinks, a water fountain and restrooms. The park has some volleyball courts (bring your own net and ball) and is about a mile from El Porto beach.

giving, Christmas and New Year's. A 72-foot blue whale skeleton greets you outside; the model of a 33-foot Pacific giant squid, Chumash Indian artifacts and birds' nests filled with eggs are inside. Turn a wheel to start the wave machine, watch bees work on honeycomb and press a button to see and hear a rattlesnake replica shake its rattles. Sunday docent tours begin at 2 p.m.

Airports. At small airports, watch the planes come and go. At mid-size airports, also see the check-in counter, luggage or fuel being loaded onto waiting planes. At larger airports, see all of the above and baggage-handling equipment. conveyor belt. At some airports, you may pass through security to view airline boarding activities. Tours can often be arranged if you call ahead. Check the telephone directory for an airport near you. Hours, parking charges vary.